Drive for knitting machines



- June 1, 1937. J LAWSON r AL I 2,082,207

DRIVE FOR KNITTING MACHINES Filed Dec. 24, 1932 3 Sheets-Sheet 1 I .II E III I I W i I N [k m o Q n v P J u w i N :2] Hlll F) a Q JZHNZAWJfl/V, N 2 a N zPaaz'Rrji LAM/30M y 97 ATTY June 1, 1937.

J. LAWSON ET AL DRIVE FOR KNITTING MACHINES Filed Dec. 24, 1932 3 Sheets-Sheet 2 fjVI ENTORS. J'OHN LAX/V5015; R0551? THZA wsazz By @01 TM AT y.

June 1, 1937.

J.I AVVS()N EI'AL DRIVE FOR KNITTING MACHINES Filed Dec. 24, 1932 3 Sheets-Sheet 3 fNI/E/VTORS: .To HIV LA wsozv,

Patented June 1, 1937 UNITED STATES 2,082,207 DRIVE FOR KNITTING MACHINES John Lawson, Bristol, and Robert H.'Lawson,

Pawtucket, R. L, assignors to Hemphill Company, Central Falls, Massachusetts R. I., a corporation of Application December 24, 1932, Serial No. 648,818

2 Claims.

This invention relates to a knitting machine and more especially to a knitting machine of the so-called Burson or Lamb type, i. e., to a knitting machine having two fiat needle beds in which the needles are independently slidable to and from yarn taking position.

In the drawings:

Fig. 1 is a view in plan showing means for reciprocating the cam carriages which control the movements of the needles and sinkers, and also feed the yarns to the needles;

Fig. 2 is a fragmentary detail view partly in section showing a bearing for the shaft of the drum which controls the reciprocatory movements of the cam carriage;

Fig. 3 is a view in side elevation and corresponding to Fig. 1, certain of the parts being omitted;

Fig. 4 is a view in end elevation of the structure shown in Figs. 1 and 3; and

Fig. 5 is a view showing the cam grooves in the drum developed.

A pulley l which is driven to rotate in the direction of the arrow, Fig. 1, is fast to a shaft 2 which is mounted in tubular bearings 3 and 4 constituted by bracket arms carried by the machine frame. The shaft 2 is prevented from endwise movements in the bearings as by means of collars 5 which abut the bearings 3 and 4 and are retained in position on the shaft 2 by means of set screws 5'. At the other end of the shaft 2 is affixed a bevel gear 6 which meshes with a bevel gear 1 fast to a shaft 8. Mounted upon and connected to the shaft 8 to turn therewith, at a uniform speed, is a drum 9 the functions of which will hereinafter be described. Adjacent to the gear I the shaft is mounted in a suitable bearing l0 provided by a bracket H. The shaft 8 at its other end projects beyond the drum 9 being reduced as at l2 such reduced end being mounted in a ball bearing support (3 consisting of collars l4 and I5 between which are ball bearings I6. The collar I5 is seated in a recess 11 provided in a bracket l8 which bracket upstands from the machine frame and is provided at its upper end with two diverging arms 19 and 20. The collar I5 is retained in position in recess IT as by means of an overlapping ring 2| which ring is made fast to the outer face of the bracket [8 as by means of screws 22 and 23. The screws or bolts 23 are long, their other ends 24 being in engage ment with a thrust plate 25 while their outer, threaded ends 26 are in threaded engagement with holes provided in the ring 2|, nuts 21 also being in threaded engagement with the outer ends 26 and in engagement with the outer face of the ring 2|.

The bearing construction just described constitutes a thrust support or bearing for the drum 9, one 'face thereof being normally in engagement with an adjacent face of the plate 25 as at 28. When assembled, the screws or bolts 23 are inserted in their respective holes in the bracket I8 until their ends 24 come into engagement with the plate 25 and when such plate is positioned in the proper relative position against the drum 9 as indicated in Fig. 2, the nuts 21 are screwed onto the ends 26 of the bolts thus locking the screws 23 in position. Thus it will be seen that when the parts are in the assembled position shown in Fig. 2, any tendency of the drum 9 to move tothe left, Fig. 2, will be resisted by the plate 25 which in turn is prevented from moving in'the said direction by the threaded engagement between the bolts 23 and the ring 2 I.

The arms 19 and 20 of the bracket l8 terminate in hubs 29 and 30 through which pass rods or shafts 3| and 32. The shafts 3| and 32 provide sliding supports for cam carriages 33 and 34 which cam carriages as usual in the Burson or Lamb type of machines carry the cams for controlling the needles as well as sinker cams and yarn guides. To the underside of the cam plates 33 and 34 are connected brackets, such as 35 by means of screws or bolts 36, to which brackets is connected a transversely extending bar 31 itself connected as by means of set screws 38 to tubular members 39; 49 which surround the respective shafts 3|, 32v and slide thereon thus supporting the cam carriages and connected parts for sliding movements lengthwise of the needles (not shown). Connected to the bar 31 midway the length thereof by means of screws 4! is a bracket 42, the bracket including a laterally extending portion 43 through which is a hole and within which hole is swiveled a shaft 44 which is retained in position by means of a co1lar'45 connected thereto in any suitable manner. shaft 44 terminates adjacent to its lower end in an enlarged portion 46 which prevents upward movement of the shaft through the bracket. At the lower end of the shaft 44 is connected a cam follower or shoe 4! the function of which will be presently described.

Connected to the respective cam carrying slides 33 and 34 are brackets 48 and 48' which at their The upper ends are recessed or notched as at 49, withi in which recesses a bar 50 is inserted. To the bar are reciprocated back and forth with respect to the needles, but as the present invention is primarily concerned with the means for reciprocating the cam carriages and parts connected thereto and not to such parts per se, further description thereof will be omitted.

The rods 3| and 32 are supported at their ends in bearings 29, 29, 30, 30, screws connected to the bars 3|, 32 preventing endwise movement thereof in the respective bearings 29, 29, 30, 30. The bearings 29, 30 are, as hereinbefore described, parts of bracket |8 and likewise the bearings 29', 39 are parts of the bracket The cam follower or shoe 4! rides in a cam track indicated by the numeral 5| and, assuming the direction of the rotation of the drum 9 to be in the direction of the arrow, Fig. 1, and the position, Fig. 1, to be the starting position, such starting position in Fig. 5 would be at about the point indicated by the numeral 52. Rotation of the drum 9 in the direction indicated by the arrow 53, Fig. 5 causes the cam follower 41 to move along the cam track 5| in the direction indicated by the arrow 54, the successive positions of cam follower 41 being indicated by the arrows 55, 55, 57, 58, 59, 60, 6|, 62, 63 and 64 after which the cam follower again assumes the initial position shown in Fig. 1. Thus it will be understood that four complete rotations of the drum 9 are required to cause the follower to make a complete cycle, i. e., start from the point indicated by the arrow 52 and return to the same point. Furthermore, much the greater portion of the traverse of the follower cross-wise of the drum 9 is effected during a single revolution, the follower dwelling at or adjacent to one end of the drum 9 during one complete revolution of the drum. Evidently by controlling the movements of the follower 41 in the manner just described, the dwell at each end of the drum avoids any sudden shocks that would otherwise result from a quick reversal in the direction of movement of the follower 41 and parts connected thereto.

As will be observed by inspecting Figs. 1, 3 and 5, when proceeding along the portions of the cam track 5| indicated by the arrow 54, the cam follower 41 and consequently the carriages- 33 and 34, are just commencing to move toward the right, Fig. 1. As the cam follower 4! approaches and enters the portion of the cam track 5| indicated by the arrow 55, the movement of said cam follower 41 and connected parts is being accelerated appreciably, and by the time the said cam follower is moving along the portion of the cam track indicated by the arrows 56 and 5'! the maximum speed of traverse of the cam carriages is attained. Thereafter as the cam follower 41 enters the portion of the cam track adjacent to the arrow 58, the speed of the cam carriers 33 and 34 is decreased until the movement of the cam carriers 33 and 34 in the direction to the right, Fig. 1, is arrested by the portion of track 5| indicated by arrow 59. The said cam carriers then begin to retrace their movements to the left, Fig. 1, as the follower 41' enters the portion of the cam track adjacent to the arrow 60, the movement of the cam carriers being sharply accelerated as the follower 4'! travels along the portions of the cam track adjacent to the arrows GI and 62. When the follower 47 reaches the portion of the cam track adjacent to the arrow 63, the speed of traverse of the cam carriers 33 and 34 is materially reduced. Finally,

after the follower enters the portion of the cam track indicated by the arrow 64 and approaches the starting point, the traverse of the cam carriers 33, 34 to the left, Fig. 1, is halted, after which the cycle just described is repeated.

The movements just described are due to the cam grooves in the drum 9 being disposed at or substantially at right angles with respect to the axis of the drum at points adjacent to each end of the latter and being disposed at points intermediate the ends of the drum at lesser angles with respect to the said axis.

In the foregoing description of the operation,

it will be evident that the drive for reciprocating the cam carriers and connected parts, is such as to obtain a maximum speed of traverse in both directions of reciprocation, while, at the same time, sharply decreasing the speed of traverse adjacent to both ends of travel of the cam carriers and connected parts. This construction avoids the usual shocks attendant upon quick reversals of the relatively heavy cam carriers, and at the same time so accelerates the speed of traverse of the cam carriers between the ends of the drum 9 as to increase substantially the production of each machine.

We claim:

1. In a knitting machine a rotary drum and means providing a thrust bearing therefor, said means including a drum shaft and a bracket having mounted therein a bearing for the said shaft, a thrust plate and means including a pin passing through the bracket, and connected thereto in such a manner as to be prevented from endwise movement therethrough, for maintaining the thrust plate in position to limit the movement of the drum in the direction thereof.

2. A flat bed knitting machine having independent needles and reciprocatory cams for effecting the knitting of fabric, means for effecting such reciprocations and including a rotary drum having cam paths that cross at three points only, the construction of the drum being such as to cause the greater portion of the traverse to be effected during one complete revolution of the drum and to cause the reciprocating parts to move at such a greatly reduced reciprocating speed during the following complete rotation of the drum that the employment of means to reduce the shock at the end of each reciprocatory movement is avoided.

JOHN LAWSON. ROBERT E. LAWSON. 

